JP7237561B2 - Stirrer and Stirrer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a stirring blade and a stirring device.

2. Description of the Related Art A stirring device having a stirring blade is used as a device for stirring, such as dispersing and mixing, a liquid or a mixture of powder and liquid. Patent Literature 1 discloses an example of a conventional stirring blade and stirring device. In the configuration disclosed in this document, a rotating blade is attached to the tip of a rotating shaft that is driven to rotate. The rotating blades are rotated in the container containing the object to be stirred to perform agitation such as dispersing and mixing the object to be stirred.

Here, stirring is a concept including dispersion and mixing. Dispersing an object to be stirred is an operation of dispersing another substance (eg, liquid or powder) in a microscopic state in a substance (eg, liquid) that is chemically in one phase. Further, mixing the object to be stirred means the operation of stirring the object to be stirred in the container so that the object to be stirred has a more uniform property. In order to improve the dispersion in the stirring device, it is important to concentrate the force of the stirring blades on a very small part of the object to be stirred, and in many cases the force acts on a region very close to the stirring blades. On the other hand, in order to improve the mixing in the stirring device, it is important to apply the force of the stirring blades to the entire object to be stirred contained in the container to make it flow. In this way, it is required to achieve both contradictory behaviors in order to enhance dispersion and mixing with one stirring blade. In particular, the higher the viscosity of the object to be stirred, the more difficult it is to improve dispersion and mixing.

The stirring blade disclosed in Patent Document 1 is formed to have a base and a plurality of blades connected to the base by appropriately cutting and bending a plate material made of a single metal material. . In order to achieve a higher level of stirring, it is necessary to set the shape, size, angle, etc. of the blades in various ways. However, the shape, size, angle, etc. of the wing portion obtained by cutting and bending a plate material made of a single metal material are naturally limited. Further, if the blades are made larger or stand up more, there is a concern that the support of the blades by the base may be insufficient.

As effective means for solving this problem, the inventors of the present application have proposed the stirring blade and stirring device disclosed in Patent Document 2. This stirring blade is a stirring blade that is rotated around the axial direction, and comprises a base portion and a blade group consisting of a plurality of blade portions positioned on one side in the axial direction with respect to the base portion and arranged in the direction of rotation. The blade portion has a front curved portion which is connected to the inner end in the radial direction and which is convex forward in the rotational direction when viewed in the axial direction.

One of the reasons for the advanced mixing by the stirring blades of Patent Document 2 is the contribution of the forward curved portion of the blades. According to the inventors' verification, by making the front curved portion convex forward in the rotational direction, the object to be processed is strongly attracted at the inner end, and furthermore, the rear curved portion is provided which is convex backward in the rotational direction. As a result, the sucked object to be processed moves radially outward more smoothly, thereby enhancing dispersion and mixing.

However, since the stirring blades of Cited Document 2 have a complicated shape, they must be manufactured as a whole by cutting, casting, 3D printers, or the like, which raises the problem of manufacturing costs. As a method of solving this problem, a method of separately fabricating the base and the blades and joining the blades to the base by welding or the like can be considered, but this method can solve the problem of manufacturing costs. However, there arises a problem that stirring performance equivalent to that of stirring blades manufactured by cutting or the like cannot be obtained.

JP-A-10-180073 International Publication No. 2017/212935

The present invention is intended to solve the above problems, it is possible to manufacture a stirring blade at a low cost, and to stir by a method in which a base and a blade are separately produced and the blade is joined to the base by welding or the like. To provide a stirring blade having the same stirring performance as a stirring blade manufactured entirely by cutting, casting, or a 3D printer even if the blade is manufactured, and to provide a stirring device using the blade.

Specifically, the stirring blade of the present invention rotates around an axis, comprises a plurality of first blades and second blades provided on a base and arranged around the axis, wherein the first blade Each of the portion and the second blade portion has an inner end in a radial direction perpendicular to the axis, and a forward curved portion connected to the inner end and convex forward in the direction of rotation about the axis. , the base has a first side and a second side in a direction parallel to the axis, the first blades are provided on the first side and arranged around the axis; Two blade portions are stirring blades provided on the second side and arranged around the axis, wherein the shape of the first side of the base is tapered in one direction parallel to the axis. The shape of the second side of the base is a truncated cone that tapers in the other direction parallel to the axis, and the first blade portion is the first side and the second blade portion is joined to the inclined surface of the second side, and the first blade portion and the second blade portion are a plurality of surface portions having different inclination angles in the rotation direction. The surface portions are configured such that the adjacent surface portions are connected to each other via a bent portion, and the surface portions of the first blade portion and the second blade portion are arranged closer to the center of the base portion. It is inclined to be located forward in the rotational direction, and among the surface portions of the first blade portion, the surface portion located at the end on the center side of the base portion extends to the upper bottom surface of the first side of the base portion. Among the surface portions of the second blade portion, the surface portion positioned at the center side end of the base portion extends to the upper bottom surface of the second side of the base portion (claim 1 ).

Preferably, each of the first blade portion and the second blade portion has a rear curved portion that is connected to the front curved portion outward in the radial direction and convex rearward in the rotational direction (claim 2 ). . More preferably, the position of the first blade portion in the rotational direction is different from the position of the second blade portion (Claim 3).

Further, the stirring device of the present invention comprises the stirring blades, a container for containing the object to be stirred, and a rotating shaft inserted into the container and to which the stirring blades are attached (claim 4 ).

According to the present invention, the stirring blade can be manufactured at low cost, and even if the stirring blade is manufactured by a method in which the base and the blade are separately manufactured and the blade is connected to the base by welding or the like, It is possible to provide a stirring blade having the same stirring performance as a stirring blade manufactured entirely by cutting, casting, or a 3D printer, and a stirring device using the blade.

Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

1 is a perspective view showing a stirring blade according to the present invention; FIG. 1 is a front view showing a stirring blade according to the present invention; FIG. 1 is a plan view showing a stirring blade according to the present invention; FIG. FIG. 4 is a perspective view showing a stirring blade according to another embodiment of the present invention;

Preferred embodiments of the present invention will be specifically described below with reference to the drawings. 1 to 3 show one embodiment of the stirring blade according to the present invention, and FIG. 4 shows another embodiment of the stirring blade according to the present invention.

FIG. 1 is a perspective view showing the stirring blade A1. FIG. 2 is a front view showing the stirring blade A1. FIG. 3 is a plan view showing the stirring blade A1 viewed from above in the z direction in FIGS. 1 and 2. FIG. The rotation direction θ is the direction in which the stirring blade A1 rotates, and is generally called the circumferential direction with respect to the axial direction z and the radial direction r.

The stirring blade A1 is attached to the stirring device disclosed in Patent Document 2 (see FIGS. 13 and 24 of the same document) to constitute the stirring device B1. The stirrer B1 has a container, a rotating shaft and a driving part. The container contains an agitation object to be dispersed and mixed. A stirring blade A1 is attached to the end of the rotating shaft, and the rotating shaft is inserted into the stirring object of the container. The driving section rotates the rotating shaft in the axial direction, and includes, for example, a motor.

As a structure for attaching the stirring blade A1 to the rotating shaft of the stirring device B1, various attachment mechanisms such as an engaging mechanism and a fastening mechanism may be adopted, and the rotating shaft and at least a part of the stirring blade A1 are integrated. It may be a structure formed in the

As shown in FIGS. 1 to 3, the base 1 is tapered in the axial direction z, and the base 3 is tapered in the direction opposite to the axial direction z, each of which has an inclined surface 11, 31. is a truncated cone with A plurality of blade portions 2 and 4 are supported in a state of being arranged at regular intervals on inclined surfaces 11 and 31 of base portions 1 and 3, respectively. The base portion 1 and the base portion 3 are connected in a spaced apart state with respect to the axial direction z by a connecting portion 5 arranged concentrically with the rotating shaft.

The blade portion 2 and the blade portion 4 are provided at positions shifted in the rotation direction θ. In the illustrated example, the blade portion 2 and the blade portion 4 are arranged at positions shifted by 45 degrees (90 degrees/2) in the rotation direction θ.

All of the plurality of blade portions 2 and 4 have the same shape and are bent by bending portions 23 and 43 . In the illustrated example, the blades 2 and 4 have three bent portions 23 and 43 per blade, and four flat areas (surface portions 24 and 44) defined by the bent portions 23 and 43. Owned. Further, the surface portion 24 is inclined forward in the rotational direction θ as the surface portion 24 is positioned in the axial direction z and the surface portion 44 is positioned in a direction opposite to the axial direction z. The surface portions 24 and 44 are not limited to flat plate-shaped portions, and may be curved plate-shaped. 2 and 3, the bent portions 23 and 43 are omitted for the sake of convenience.

The wings 2,4 have inner ends 21,41. The inner end 21 is the innermost end of the blades 2 and 4 in the radial direction r. In the illustrated example, the inner ends 21,41 coincide with the junctions of the vanes 2,4 and the inclined surfaces 11,31 of the bases 1,3.

The number of vanes 2 and 4 arranged on bases 1 and 3 is not particularly limited. In the stirring blade A1, there are four blade portions 2 and four blade portions 4, respectively. The blades 2 and 4 are arranged at an equal pitch, and in the illustrated example, the pitch is 90 degrees.

The blades 2 and 4 have front curved portions and rear curved portions (not shown). The front curved portion and the rear curved portion can be defined in the same manner as the definition method described in Patent Document 2. The front curved portion is a portion connected to the inner ends 21 and 41 and convex forward in the rotation direction θ when viewed in the axial direction z. is convex forward in the rotational direction θ from the imaginary straight line connecting the . In this embodiment, the front curved portion is composed of two regions of the face portion 24 located on the z-axis side and two regions of the face portion 44 located on the opposite side to the z-axis direction.

The rear curved portion is a portion that extends outward in the radial direction r from the front curved portion and projects rearward in the rotational direction θ when viewed in the axial direction z. More specifically, the rear curved portion has a shape projecting rearward in the rotational direction θ from an imaginary straight line connecting both ends in the radial direction r of the rear curved portion. In this embodiment, the rear curved portion is composed of two regions of the surface portion 24 located on the opposite side of the axial direction z, and two regions of the surface portion 44 located on the axial direction z side.

Materials for forming the bases 1 and 3 and the blades 2 and 4 are not particularly limited, and preferred examples thereof include metal materials such as stainless steel.

The stirring blade A1 is manufactured by a method in which the bases 1, 3 and the blades 2, 4 are produced separately and joined together. As a joining method, mechanical joining (shrink fitting, caulking, etc.), chemical joining (adhesion, etc.), metallurgical joining (fusion welding, pressure welding, brazing, etc.) can be used. In this embodiment, they are joined by welding (fusion welding). The base 1 and the base 3, to which the blades 2 and 4 are welded as described above, are connected in a spaced-apart manner with respect to the axial direction z by the connecting portion 5 arranged concentrically with the rotating shaft. The connection method is not particularly limited, and joining, screwing, or the like can be used.

The bases 1 and 3 can be produced by machining (cutting, forging, etc.), casting, 3D printing, or the like. In this embodiment, it is made by cutting.

The vanes 2 and 4 can be produced by machining or the like. In this embodiment, it is produced by punching and bending.

Next, the action of the stirring blade A1 will be described.

As a factor of the high mixing by the stirring blade A1, first, the contribution of the front curved portions of the blades 2 and 4 can be mentioned. According to the research of the inventors, by making the front curved portion convex forward in the rotation direction θ, the object to be stirred is more strongly sucked at the inner ends 21 and 41, and the sucked object to be stirred is moved outward in the radial direction r. The knowledge that it is possible to move more smoothly in the direction was obtained. This strong suction and smooth movement are considered to be one of the factors that cause the entire object to be stirred to be mixed.

In addition, according to the research of the inventors, by providing a rear curved portion that is convex backward in the rotation direction θ, the effect of more forcefully discharging the sucked object to be stirred from the stirring blade A1 in the radial direction r outward can be obtained. It turned out to be The synergistic effect of the enhancement of suction by the front curved portion and the enhancement of discharge by the rear curved portion can promote mixing of the entire object to be stirred.

In addition, by tilting the blades 2 and 4 forward in the rotation direction θ, it is possible to prevent the air bubbles mixed in the object to be stirred from remaining behind in the rotation direction θ of the blades 2 and 4 . The stagnation of air bubbles can be a factor that hinders mixing of the object to be stirred by the stirring blade A1. According to the stirring blade A1, it is possible to suppress the remaining air bubbles, which is preferable for enhancing the mixing of the object to be stirred.

FIG. 4 is a perspective view showing the stirring blade A2. The rotation direction θ is the direction in which the stirring blade A2 rotates, and is generally called the circumferential direction with respect to the axial direction z and the radial direction r. Also, the arrows in these figures indicate the direction in which the stirring blade A2 rotates.

As shown in FIG. 4, the stirring blade A2 has the same structure as the stirring blade A1, except that the stirring blade A2 is composed only of the base portion 1 and the blade portion 2 of the stirring blade A1. The stirring blade A2 is attached to the stirring device disclosed in Patent Document 2 (see FIG. 4 of the same document) to constitute the stirring device B2.

The stirrer B2 has a container, a rotating shaft and a driving part. The container contains an agitation object to be dispersed and mixed. A stirring blade A2 is attached to the end of the rotating shaft, and the rotating shaft is inserted into the stirring object of the container. The driving unit rotates the rotating shaft in the axial direction, and includes, for example, a motor. As a structure for attaching the stirring blade A2 to the rotating shaft of the stirring device B2, various attachment mechanisms such as an engaging mechanism and a fastening mechanism may be adopted, and the rotating shaft and at least a part of the stirring blade A2 may be integrated. It may be a structure formed in

The stirring device according to the present invention is not limited to the embodiments described above. The specific configuration of each part of the stirring device according to the present invention can be changed in various ways.

A1, A2: stirring blades B1, B2: stirring device 1: base 2: blade 3: base 4: blade 5: connecting portion 11: inclined portion 21: inner end 22: surface portion 23: bent portion 31: inclined portion 41 : Inner end 42 : Surface portion 43 : Bent portion r : Radial direction z : Axial direction θ : Rotational direction

Claims (4)

rotate around an axis,
comprising a plurality of first blades and second blades provided on the base and arranged around the axis;
Each of the first blade portion and the second blade portion has an inner end in a radial direction perpendicular to the axis, and a forward curved portion connected to the inner end and projecting forward in the direction of rotation about the axis. and
the base has a first side and a second side in a direction parallel to the axis;
The first blade portion is provided on the first side and arranged around the axis, and the second blade portion is a stirring blade provided on the second side and arranged around the axis,
The shape of the first side of the base is a truncated cone that tapers in one direction parallel to the axis,
the shape of the second side of the base is a truncated cone that tapers in the other direction parallel to the axis;
The first blade portion is joined to the first-side inclined surface, and the second blade portion is joined to the second-side inclined surface,
The first blade portion and the second blade portion are composed of a plurality of surface portions having different inclination angles in the rotation direction,
Adjacent surface portions of the surface portions are connected to each other via a bent portion,
The surface portions of the first blade portion and the second blade portion are inclined so that the surface portion located closer to the center of the base portion is located forward in the rotation direction,
Among the surface portions of the first blade portion, the surface portion located at the center side end of the base portion extends to the upper bottom surface of the first side of the base portion,
A stirring blade characterized in that, of the surface portions of the second blade portion, a surface portion located at an end on the center side of the base portion extends to an upper bottom surface of the second side of the base portion. 2. The stirring according to claim 1, wherein each of the first blade portion and the second blade portion has a rearward curved portion connected to the forward curved portion outwardly in the radial direction and convex rearward in the rotational direction. Feather. The stirring blade according to claim 1 or 2, wherein the first blade portion is different in position in the rotation direction from the second blade portion. A stirring blade according to any one of claims 1 to 3;
a container that accommodates an object to be stirred;
a rotating shaft inserted into the container and to which the stirring blades are attached;
A stirring device.

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